GMR Technology

"GMR switches are small sensors whereby the presence of a magnetic field changes the resistance of the sensor’s magneto resistive material, this is sensed as a change in output voltage by a comparator which operates a transistor"

GMR (GIANT MAGNETO RESISTIVE) WHAT IS IT ?
Magneto Resistive Technology derives its name from a class of materials that change resistance in the presence of a magnetic field. Giant Magneto Resistive, which was developed in 1988, is an advanced application of magneto resistive technology. GMR Sensors are composed of alternating layers of conductive magnetic and non magnetic material. As a magnetic field passes in proximity of the GMR sensor the resistance changes. A linear output signal is produced by utilising four GMR resistors in a wheatstone bridge configuration.

This voltage is then amplified, sent to a comparator which in turn switches the sensor output as it detects the magnetic field. All ULTRALINE solid state sensors utilise GMR technology in its sensor products.

This technology offers a number of advantages over widely used Hall Effect and AMR (Anisotropic Magneto Resistive) senors.